Atomistic insight into welding silver nanowires and interfacial characteristics of the welded zone

Silver nanowires (Ag-NWs) could be welded together to form a network of silver nanowires in nanodevice fabrication. This study looks into the effect of capillary depth, crystalline orientation, and a heat source or mechanical vibration assistance on the welding process of Ag-NWs. According to the findings, increasing capillary depth causes higher levels of lattice distortion, dislocation density, atomic strain, and residual stress. The capillary depth should be sufficient to form a strong welding joint. Notably, the welding joints of Ag-NWs could recover at room temperature, demonstrating the advantage of the nanowires' cold welding. The Ag welding joint could achieve the highest UTS value of 3.83 GPa. Furthermore, changing the orientation of Ag-NWs may affect the welding joint properties. The orientation (001) welding joint has a better crystalline structure and UTS value than orientations (110) and (111). Moreover, the sample with a higher temperature has a superior diffusion rate and smoother force diagram than the lower one. At higher temperatures, the FCC crystalline structure of the original Ag-NWs is more easily transformed into HCP and amorphous structures. In addition, because Ag-NWs are ductile, vibration-assisted welding causes less structural damage than temperature-assisted welding. The UTS of the 10 angstrom amplitude has the highest value of 4.28 GPa. Applying vibration in a suitable amplitude could both facilitate diffusion while conserving the crystalline structure. The UTS value could be improved with appropriate vibration conditions.